func writeSocks4Response(writer io.Writer, errCode byte, address v2net.Address, port v2net.Port) error {
buffer := buf.NewLocal(32)
buffer.AppendBytes(0x00, errCode)
buffer.AppendSupplier(serial.WriteUint16(port.Value()))
buffer.Append(address.IP())
_, err := writer.Write(buffer.Bytes())
return err
}
func appendAddress(buffer *buf.Buffer, address v2net.Address, port v2net.Port) {
switch address.Family() {
case v2net.AddressFamilyIPv4:
buffer.AppendBytes(0x01)
buffer.Append(address.IP())
case v2net.AddressFamilyIPv6:
buffer.AppendBytes(0x04)
buffer.Append(address.IP())
case v2net.AddressFamilyDomain:
buffer.AppendBytes(0x03, byte(len(address.Domain())))
buffer.AppendSupplier(serial.WriteString(address.Domain()))
}
buffer.AppendSupplier(serial.WriteUint16(port.Value()))
}
func (request *Socks5UDPRequest) Write(buffer *buf.Buffer) {
buffer.AppendBytes(0, 0, request.Fragment)
switch request.Address.Family() {
case v2net.AddressFamilyIPv4:
buffer.AppendBytes(AddrTypeIPv4)
buffer.Append(request.Address.IP())
case v2net.AddressFamilyIPv6:
buffer.AppendBytes(AddrTypeIPv6)
buffer.Append(request.Address.IP())
case v2net.AddressFamilyDomain:
buffer.AppendBytes(AddrTypeDomain, byte(len(request.Address.Domain())))
buffer.Append([]byte(request.Address.Domain()))
}
buffer.AppendSupplier(serial.WriteUint16(request.Port.Value()))
buffer.Append(request.Data.Bytes())
}
func EncodeUDPPacket(request *protocol.RequestHeader, payload *buf.Buffer) (*buf.Buffer, error) {
user := request.User
rawAccount, err := user.GetTypedAccount()
if err != nil {
return nil, errors.Base(err).Message("Shadowsocks|UDP: Failed to parse account.")
}
account := rawAccount.(*ShadowsocksAccount)
buffer := buf.NewSmall()
ivLen := account.Cipher.IVSize()
buffer.AppendSupplier(buf.ReadFullFrom(rand.Reader, ivLen))
iv := buffer.Bytes()
switch request.Address.Family() {
case v2net.AddressFamilyIPv4:
buffer.AppendBytes(AddrTypeIPv4)
buffer.Append([]byte(request.Address.IP()))
case v2net.AddressFamilyIPv6:
buffer.AppendBytes(AddrTypeIPv6)
buffer.Append([]byte(request.Address.IP()))
case v2net.AddressFamilyDomain:
buffer.AppendBytes(AddrTypeDomain, byte(len(request.Address.Domain())))
buffer.Append([]byte(request.Address.Domain()))
default:
return nil, errors.New("Shadowsocks|UDP: Unsupported address type: ", request.Address.Family())
}
buffer.AppendSupplier(serial.WriteUint16(uint16(request.Port)))
buffer.Append(payload.Bytes())
if request.Option.Has(RequestOptionOneTimeAuth) {
authenticator := NewAuthenticator(HeaderKeyGenerator(account.Key, iv))
buffer.SetByte(ivLen, buffer.Byte(ivLen)|0x10)
buffer.AppendSupplier(authenticator.Authenticate(buffer.BytesFrom(ivLen)))
}
stream, err := account.Cipher.NewEncodingStream(account.Key, iv)
if err != nil {
return nil, errors.Base(err).Message("Shadowsocks|TCP: Failed to create encoding stream.")
}
stream.XORKeyStream(buffer.BytesFrom(ivLen), buffer.BytesFrom(ivLen))
return buffer, nil
}
func WriteTCPRequest(request *protocol.RequestHeader, writer io.Writer) (buf.Writer, error) {
user := request.User
rawAccount, err := user.GetTypedAccount()
if err != nil {
return nil, errors.Base(err).Message("Shadowsocks|TCP: Failed to parse account.")
}
account := rawAccount.(*ShadowsocksAccount)
iv := make([]byte, account.Cipher.IVSize())
rand.Read(iv)
_, err = writer.Write(iv)
if err != nil {
return nil, errors.Base(err).Message("Shadowsocks|TCP: Failed to write IV.")
}
stream, err := account.Cipher.NewEncodingStream(account.Key, iv)
if err != nil {
return nil, errors.Base(err).Message("Shadowsocks|TCP: Failed to create encoding stream.")
}
writer = crypto.NewCryptionWriter(stream, writer)
header := buf.NewLocal(512)
switch request.Address.Family() {
case v2net.AddressFamilyIPv4:
header.AppendBytes(AddrTypeIPv4)
header.Append([]byte(request.Address.IP()))
case v2net.AddressFamilyIPv6:
header.AppendBytes(AddrTypeIPv6)
header.Append([]byte(request.Address.IP()))
case v2net.AddressFamilyDomain:
header.AppendBytes(AddrTypeDomain, byte(len(request.Address.Domain())))
header.Append([]byte(request.Address.Domain()))
default:
return nil, errors.New("Shadowsocks|TCP: Unsupported address type: ", request.Address.Family())
}
header.AppendSupplier(serial.WriteUint16(uint16(request.Port)))
if request.Option.Has(RequestOptionOneTimeAuth) {
header.SetByte(0, header.Byte(0)|0x10)
authenticator := NewAuthenticator(HeaderKeyGenerator(account.Key, iv))
header.AppendSupplier(authenticator.Authenticate(header.Bytes()))
}
_, err = writer.Write(header.Bytes())
if err != nil {
return nil, errors.Base(err).Message("Shadowsocks|TCP: Failed to write header.")
}
var chunkWriter buf.Writer
if request.Option.Has(RequestOptionOneTimeAuth) {
chunkWriter = NewChunkWriter(writer, NewAuthenticator(ChunkKeyGenerator(iv)))
} else {
chunkWriter = buf.NewWriter(writer)
}
return chunkWriter, nil
}